[fireyice01]

So, I was wondering if someone could break down the production of Sulfuric Acid for someone to make in their backyard? I live in a semi-wilderness area, and have been looking for alternatives to gasoline for fueling my tractors and other yard equipment, and ethenol seems to be the most viable solution. For many materials, fermenting is easy, and distillation is a fairly straightforward process, but one material in particular interests me, cellulose materials, such as newspaper and wood shavings. After reading this http://journeytoforever.org/biofuel_library/ethanol_sawdust.html I wondered how practical it would be to produce my own acid.

I know this isn't a simple process, and don't expect someone to have a quick and easy solution, but for someone that wants to make acid on a fairly large scale (enough to fuel my yard tools, and possibly my racecar) is this possible, with proper safety precautions, to do at home?

[Borek]

No idea about making sulfuric acid in the backyard - I am sure it'll be cheaper to buy.

I must say I have browsed first part of the recipe - and I don't like it. IMHO it is full of errors, mistakes and omissions to the point where it is impossible to follow. For example - how much acid per gallon of sawdust? This is crucial information, yet it is not given.

Then - process IS wrong. You can't hydrolize cellulose to simple sugars using concentrated sulfuric acid - it'll just dehydrate it, that's where the organic carbon (coal lumps) is from. Then there will be some hydrolysis, but you don't want some, you need as much as possible. For sure such process requires at least some water in which reaction takes place, not dry sawdust. Neutralization by dilution won't work (not to mention the fact, that pH of used water - as long as it is not some volcaninc or industrial dump - can be for all practical purposes neglected). And so on.

It simply won't work this way.

[hmx9123]

Sulfuric acid is one of the hard ones to make.  You have to burn sulfur, make sure you get SO3, but not SO2 (by keeping an excess of oxygen around), and then keeping the SO3 at a high enough temperature it didn't polymerize before you ran it through water to get a concentrated acid solution (which would take forever and a day).  The glass distillation setup, plus an oxygen tank or generator, plus burning the sulfur = mega pain in the ass.  It's fine for industry, but really crappy for the individual.

[NickNick]

But what about the method shown here:
http://cavemanchemistry.com/cavebook/chsaltpeter3.html

Looks pretty easy to me.

[hmx9123]

Yeah, but are you talking about making like a mL or two or are you talking about making a sizeable quantity?  The pop bottle method is not going to give you lots of material, and it's time-intensive.

[NickNick]

I'll be doing it soon with photos of it on my website and a little video showing the sulfur ignite. I will repeat the procedure several times on 100ml of water and then evaporate the water to see how much oily sulfuric acid is left.

But the beauty of it is that I only need the acid for dissolving metals, and diluted sulfuric acid reacts more strongly with metal than pure sulfuric acid. For instant, a 20% solution dissolves metal much faster and more vigorously than a 90% solution. This is because sulfuric acid needs water to work.

Also, the alchemists made their sulfuric acid by heating iron sulfides.

[Borek]

Burning sulfur will give you sulfurous acid, not sulfuric.

[hmx9123]

If you want dilute sulfuric, why don't you go down to Auto Zone and pick up a bag of 'battery electrolyte'.  That's just moderate concentration sulfuric.

[AWK]

Hydrolysis of cellulose needs a catalytic amouns of sulfuric acid. Each car battery contains amounts of sulfuric acid sufficient for hydrolysis of a huge amount of cellulose.

[NickNick]

Burning sulfur will give you sulfurous acid, not sulfuric.

Uh yeah I know that, but I was reffering to the Lead Chamber process which burns sulfur with sodium nitrate. The sulfur dioxide is converted to sulfur trioxide which then reacts with the water to form sulfuric acid. 

[NickNick]

I can buy sulfuric acid online if I want it, but it will be the wrong kind. And I have a bottle of concentrated sulfuric acid from the local hardware store (drain cleaner). But the kind I need is what use to be made by the lead chamber process because that has different isomers. As I learned here, not all sulfuric acid is the same. There's a big difference depending on how it's produced. And the process I need the acid for requires it to be the lead chamber type. Normal sulfuric acid was found to be useless for this.

[AWK]

What do you mean by a normal type of sulfuric acid?

[macman104]

What do you mean by a normal type of sulfuric acid?

I believe he's referring to the information Valdo gave him here

Also, the article Valdo references is located here

EDIT:  However, the article only address the hydration of sulfuric acid (and the difference between the cis/trans forms), I was not able to locate information about how the process with which sulfuric acid forms influences the ratio of cis/trans isomers of sulfuric acid.

[AWK]

_{cis/trans isomers of sulfuric acid.} what does mean?

[macman104]

_{cis/trans isomers of sulfuric acid.} what does mean?

I'm honestly not 100% sure.  The article seems to suggest a difference between two different forms of the sulfuric acids depending on how the hydroxyl groups are pointed at each other.

However, unlike NickNick states, I cannot find any information to indicate that one form of preparation over another creates a higher percentage of one form of the acid.